*{
    margin: 0;
    padding: 0;
}
body{
    background: black;
}


/*导航栏*/
 body , .nav , .menu {
     display: flex;
     justify-content: center;
     align-items: center;
 }
 .nav {
     position: relative;
     margin: 30px;
     background-color: #fff;
     padding: 10px;
     transform: none;
     border-radius: 50px;
     overflow: hidden;
     box-shadow: 0 8px 15px rgba(0,0,0,.2);
 }
 .menu {
     margin: 0;
     padding: 0;
     width: 0;
     overflow: hidden;
     transition: 0.5s;
 }
 .nav input:checked ~ .menu {
     width: 400px;

 }
 .menu li {
     list-style: none;
     margin: 0 10px;

 }
 .menu li a{
     text-decoration: none;
     color: #666;

     font-weight: 600;
     transition: 0.5s;

 }
 .menu li a:hover {
     color: cadetblue;
 }
 .nav input {
     width: 50px;
     height: 30px;
     cursor: pointer;
     opacity: 0;
 }
 .nav span {
     position: absolute;
     left: 20px;
     width: 30px;
     height: 4px;
     border-radius: 50px;
     background-color: #666;
     pointer-events: none;
     transition: 0.5s;
 }
 .nav input:checked ~span {
     background-color: antiquewhite;
 }
 .nav span:nth-child(2) {
     transform: translateY(-8px);
 }
 .nav input:checked ~ span:nth-child(2) {
     transform: translateY(0) rotate(-45deg);
 }
 .nav span:nth-child(3) {
     transform: translateY(8px);
 }
 .nav input:checked ~ span:nth-child(3) {
     transform: translateY(0) rotate(45deg);
 }




.box{
    position: absolute;
    left: 50%;
    top:50%;
    transform: translate(-50%,-50%);
    width: 620px;
    height: 400px;
    border: 1px solid #fff;
    box-sizing: border-box;
    box-shadow: 0 15px 25px rgba(250,250,250,.2);
    overflow: hidden;
    border-radius: 15px;
}

.about{
    position: absolute;
    padding: 10px;
    left: 50%;
    width: 600px;
    height: 300px;
    /*垂直居中*/
    top:50%;
    transform: translate(-50%,-50%);
}

.about h1{
    text-align: center;
    padding: 20px;
    color: #fff;
}


/*图片*/
.imabox{
    position: absolute;
    width: 100%;
    height: 100%;
}

.imabox::before{
    position: absolute;
    content: '';
    left: 0;
    top:0;
    width: 50%;
    height: 100%;
    background: url("../images/photo04.jpg");
    background-size: cover;
    transition: 1s;
    /*轴*/
    transform-origin: bottom;
}

.box:hover .imabox::before{
    transform: rotateX(90deg); translateY(100%)
}

.imabox::after{
    position: absolute;
    content: '';
    right:0;
    top:0;
    width: 50%;
    height:100%;
    background: url("../images/photo04.jpg");
    background-size: cover;
    transition: 1s;
    /*轴*/
    transform-origin: top;
    background-position: 397.5px;
}

.box:hover .imabox::after{
    transform: rotateX(90deg) translateY(100%);
}